Sheet folding machine



May 26, 1964 R. SJOSTROM 3,134,587

SHEET FOLDING MACHINE Filed 001:. 26. 1960 4 Sheets-Sheet 1 ROBERT L.SJOSTROM MWWW May 26, 1964 R. L. SJOSTROM SHEET FOLDING MACHINE Filed Oct. 26, 1960 4 Sheets-Sheet 2 III II FIG.2

INVENTOR. ROBERT L. SJOSTROM y 1964 R. L. SJOSTROM 3,134,587

SHEET FOLDING MACHINE Filed Oct.- 26, 1960 4 Sheets-Sheet 3 INVENTOR.

ROBERT L. SJOST ROM W W MW May 26, 1964 R. L. SJOSTROM 3,134,587

SHEET FOLDING MACHINE Filed Oct. 26, 1960 4 Sheets-Sheet 4 INVENTOR. ROBERT L. SJQSTROM United States Patent 3,134,587 SHEET FOLDING MACHINE Robert L. Sjostrom, Sjostrom Machine Co., 16th St. at 2nd Ave., Boca Raton, Fla. Filed Oct. 26, 1960, Ser. No. 65,107 4 Claims. (Cl. 270-62) The present invention relates to a sheet folding machine and more particularly to a sheet folding machine adapted to fold wide sheets of fabric or the like with a plurality of transverse folds.

It is an object of the present invention to provide a machine for folding wide sheets of material such as bed sheets and the like with a plurality of transverse folds. It is also an object of the present invention to provide a machine for neatly and rapidly folding Wide sheets of material with the folds selectively oriented. It is also an object of the present invention to provide a wide sheet folding machine which is compact, relatively inexpensive to manufacture, and is adaptable for use with associated laundry and fabricating machines.

These and other objects and advantages of the present invention will be more clearly understood when considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a schematic side elevation of the invention,

FIG. 2 is a top plan schematic view of the invention 'with portions removed for clarity of understanding, and,

FIGS. 3 to 7 inclusive are schematic views illustrating successive positions of the machine in the folding of a single wide sheet fed through the machine.

This wide folding machine is particularly useful in locations such as laundries where space is at a premium.

The forward end of the machine is indicated at 7 and the rear end of the machine is indicated at 8. As illustrated in FIGS. 1 and 2, there is provided a frame 1 preferably formed of I-beams or'the like. This frame has side members 2 and 3 and cross members adapted to support the operating mechanism. Suitable legs 4 support the side member. A platform 5 integralwith the forward legs 4 supports a drive motor. A first conveyor comprising a plurality of endless belts 11 extending around parallel rolls 12 and 13 are positioned at the rear end of the machine. Shafts on which the rolls 12 and 13 are mounted are in turn journalled at their ends by suitable journals at 20 on the frame 1. The belts 11 are driven through drive roll 13 in a clockwise direction as viewed in FIG. 1. A second conveyor 14 is positioned at the forward end of the machine 7. This second conveyor comprises the endless belts 15 which extend about rolls 17 and 18 with roll 17 driving the belt in a clockwise direction as viewed in FIG. 1. The shafts of rolls 17 and 18 are supported by journals at 21. The plane of the second conveyor is slightly inclined upwardly from the roll 17 to roll 18 as illustrated in FIG. 1.

Positioned above the adjacent ends of the first conveyor 1 and second conveyor 14 are a pair of nip rolls 25 and 26. Roll 25 is journaled slightly higher than roll 26. These rolls are supported on legs 27 and 28 respectively with the ends of the rolls 25 and 26 suitably supported in journals in turn secured to the legs 27 and 28. An idler roll 30 parallel to rolls 25 and 26 is supported above the rolls 25 and 26 with the roll 30 suitablyjournaled at its ends and with the journals in turn supported on the frame extension 31. Endless parallel belts 35 extend about rolls 25 and 30. Roll 30 is sized and positioned so that the lower portion of the endless belts 35 bear against the surface of nip roll 26.

An inclined table 36 extends forwardly and downwardly from a line of tangency with roll 26 beyond the forward end of the second conveyor 14. This table may 3,134,587 Patented May 26, 1964 ice be formed with a plurality of parallel longitudinally extending slots in its surface.

The first and second conveyors as well as rolls 25, 26 and are operatively interengaged by a drive mechanism generally illustrated at 41. This mechanism 41 has a drive source such as the motor 42 which is mounted on the platform 5. An endless chain 44 driven by a gear 43 mounted on the shaft of the motor 42 positively drives the first conveyor 1, pinch roll 25 and pinch roll 26. This endless chain 44 engages a gear 45 mounted on the axle of roll 13, idler gears 46 and 47 suitably journaled on the frame, a gear 48 secured to the axle of roll 25, and a gear 49 secured to the axle of roll 26. As viewed in FIG. 1, roll 13 is driven in a clockwise direction, roll 25 in a counter-clockwise direction, and roll 26 in' a clockwise direction.

The second conveyor 14 is operatively interengaged with the first conveyor so that the upper surface of the second conveyor 14 moves forwardly at a faster rate of speed than the forward movement of the upper surface of the first conveyor. This operation of the second conveyor is effected through a chain coupling generally illustrated at 50. The endless chain 51 engages a gear mounted on the axle of roll 13 and a gear 55 mounted on the axle of roll 17. The gear 55 is smaller than the gear mounted on roll 13.

A pressure roll 58 supported in journals 59, is positioned parallel with the upper surface of the first conveyor. A clamping mechanism generally indicated at 60 is adapted to engage the leading edge of the forwardly moving sheet after it passes under the roll 58. This clamping mechanism 60 is suitably supported on a frame extension 61 with a rotatable axle 62 journaled at its end in the frame extension 61. One end of the axle has a lever 63 secured to it. The free end of the lever is pivotally interengaged with shaft 64 of the air cylinder 65. The air cylinder 65 is rigidly secured to the side of the frame 1. The cylinder is connected by tube 66 for operation to the valve 72, in turn controlling passage of air from air pump 101.

Intermittently positioned along the axle 62 are a series of solenoid actuated clamps 67. Each of these clamps comprise a solenoid having an armature 68 carrying one jaw of the clamp. The other jaw of the clamp is formed by the L-shaped member 69. Upon actuation of the solenoid by a switch in the controller 100 the upper jaw 68 will close into a tight securing grip with the lower portion of the jaw 69. Pivotable movement of the clamp 67 through rotation of the axle 62 is effected by actuation of the hydraulic pumps 65.

Positioned immediately behind clamping mechanism 60 is an air blast tube 70. This tube is provided with a plurality of longitudinally aligneddirected perforations. The holes are substantially aligned with the open jaws of the clamps when the jaws are in the position illustrated in FIG. 1. The tube 70 is connected to an air pump 101 through three way valve 72. The valve is controlled by control means 100. When connected by the valve 72 the pump 101 causes an air blast through the holes. 1

Positioned forwardly of the clamping mechanism 60 is a lever mechanism, generally indicated at 80. This lever mechanism is provided with a transverse bar 81 with lever arms 82 secured at each end. The arms 82 are each pivotally secured, one to each side of the frame. Each of these arms 82 is secured at a fulcrum point 83 inter- 81 is adapted upon actuation of the air cylinder 84 to pivot upwardly about point 83 from a position intermediate the first and second conveyors to a position immediately adjacent and substantially intermediate rolls 25 and 26. A plurality of plates 87 interposed between the belts 11 project partially over the bar 81 to guide the sheets over it. However, on actuation of the air cylinder 84, the bar 81 will pivot out from beneath the plates 87, describing an arc, to a pinching position between the rolls 25 and 26.

A pair of microswitches 90 and 91 are positioned so as to project upwardly through the upper portion of the moving belts of the first and second conveyors respectively.

Microswitch 91 actuates the controller which in turn causes the control valve 72 to actuate cylinder 84. Microswitch 90 controls the operation of air cylinder 65, clamp 67, and air blast tube 70.

In the operation of this device the motor 42 continuously drives the first and second conveyors with the upper surfaces of the conveyors moving in a forward direction. When a fabric sheet is fed onto the first conveyor 1, it first trips microswitch 90 and then passes between the jaws of the clamp 67. The jaws of clamp 67 are closed on the sheet by the microswitch 90. Tripping of microswitch 90 also initiates the counter-clockwise rotation of axle 62 as Viewed in FIG. 3. As the clamps 67 carried by the axle 62 move in a counter-clockwise direction, having previously engaged the leading edge of the fabric material 95, a blast of air from tube 70 helps separate the fabric material as illustrated in FIG. 4. This permits the lower portion of the fabric material to move uniformly forward while theupper portion is folded backwardly as illustrated in FIG. 4. When the trailing edge of the fabric material 95 passes the switch 90 the counterclockwise rotation of the clamp stops, and the jaws open. The sheet 95 is thereby disengaged from the clamping mechanism and the clamping mechanism returns to its initial position as illustrated in FIG. 5. The fabric sheet 95 however, has been completely folded once. The fabric is then carried forwardly beyond and over the plates 87 until the leading edge is engaged by conveyor 14. The fabric sheet 95 then trips the switch 91 and air cylinder 84 is thereby actuated causing bar 81 to pivot upwardly along a dotted line as is illustrated at 93. By this time the fabric sheet has been positioned directly over the bar 81. The leverage linkage system causes the bar 81 to move upwardly between the rolls 25 and 26 carrying with it the folded sheet 95.

The bar 81 forces the fabric sheet 95 between rolls 25 and 26. Rolls 25 and 26 then pinch and transversely fold the sheet 95. The sheet 95 is carried over roll 26, by endless webs 35. The fabric material which is now folded twice slides down the table 36 to an appropriate receptacle.

The controller 100 may be of any electrical and mechanical construction which will sequentially operate the air blast tube 70, air cylinder 65, clamp 67 and air cylinder 84. Microswitches 90 and 91 are operatively connected to the controller. Tripping microswitch 90 causes the sequential closing of the jaws of clamp 67 and rotation of the axle 62. The air blast is then ejected through tube 70. Tripping switch 91 causes the cylinder 84 to pivot the bar 81.

What is claimed is:

1. A folding machine for quarter folding a sheet with two transverse folds and with the end edges of said sheet uppermost subsequent to forming said folds comprising means for flat feeding discontinuous flat sheets in at least one direction, means for engaging, raising, and securing against further movement the leading end edge of said sheet as said sheet continues to move, means for releasing and dropping said leading end edge from said last mentioned means as the trailing end edge of said sheet reaches a selected position to form a first transverse fold in said sheet with said first fold in a direction forward of said end edge with respect to the direction of said movement, means for moving said sheet in a plane angular with respect to the horizontal after said first fold is formed, means for eifecting a second transverse fold in said sheet while said sheet is moving in said angular plane and means for thereafter changing the direction of movement of said twice folded sheet from said angular plane whereby said second fold is positioned in advance of said first fold with respect to the direction of movement, and means for delivering in a second angular plane said twice folded sheet as it moves with said first transverse fold lying rearwardly and said second transverse fold lying forwardly with respect to the direction of said movement and said end edges lying over said first fold.

2. A device as set forth in claim 1 wherein said means for effecting a second transverse fold in said sheet includes means for engaging said sheet along a transverse line and an inclined conveyor belt adapted to coact with said means for engaging said moving sheet to effect said second transverse fold.

3. A device as set forth in claim 2 wherein said means for engaging said sheet for making said transverse fold includes means positioned below said moving sheet comprising a transversely extending bar, lever arms positioned at and connected normally to each end of said bar, means pivotally supporting said lever arms and means for pivoting said lever arms from a position below said sheet upwardly, and said means for delivering said twice folded sheet comprises a downwardly inclined table.

4. A folding machine for quarter folding a sheet with two transverse folds and with the end edges of said sheet uppermost subsequent to forming said folds comprising means for flat feeding discontinuous flat sheets in one direction, means for engaging, raising and securing against further movement the leading end edge of said sheet as said sheet continues to move, means for releasing and dropping said leading end edge from said last mentioned means as the trailing end edge of said sheet reaches a selected position to form a first transverse fold in said sheet with said first fold in a direction forward of said end edge with respect to the direction of said movement, means for moving said sheet in a second direction angular with respect to said first direction after said first fold is formed, means for effecting a second transverse fold in said sheet while said sheet is moving in said second direction and means thereafter changing the direction of movement of said twice-folded sheet from said second direction of movement whereby said second fold is positioned in advance of said first fold with respect to the direction of movement, and means for delivering in another direction angular with respect to said second direction said twicefolded sheet as it moves with said first transverse fold lying rearwardly and said second transverse sheet fold lying forwardly with respect to said another direction of movement and said edges lying over said first fold.

References Cited in the file of this patent UNITED STATES PATENTS 1,682,237 Osborne Aug. 28, 1928 2,022,352 Kahn Nov. 26, 1935 2,072,790 Apitsch et a1. Mar. 2, 1937 2,650,821 Howlett Sept. 1, 1953 2,811,350 Cran Oct. 29, 1957 2,821,386 Petrie Ian. 28, 1958 FOREIGN PATENTS 706,093 Great Britain Mar. 24, 1954 803,895 Great Britain Nov. 5, 1958 

1. A FOLDING MACHINE FOR QUARTER FOLDING A SHEET WITH TWO TRANSVERSE FOLDS AND WITH THE END EDGES OF SAID SHEET UPPERMOST SUBSEQUENT TO FORMING SAID FOLDS COMPRISING MEANS FOR FLAT FEEDING DISCONTINUOUS FLAT SHEETS IN AT LEAST ONE DIRECTION, MEANS FOR ENGAGING, RAISING, AND SECURING AGAINST FURTHER MOVEMENT THE LEADING END EDGE OF SAID SHEET AS SAID SHEET CONTINUES TO MOVE, MEANS FOR RELEASING AND DROPPING SAID LEADING END EDGE FROM SAID LAST MENTIONED MEANS AS THE TRAILING END EDGE OF SAID SHEET REACHES A SELECTED POSITION TO FORM A FIRST TRANSVERSE FOLD IN SAID SHEET WITH SAID FIRST FOLD IN A DIRECTION FORWARD OF SAID END EDGE WITH RESPECT TO THE DIRECTION OF SAID MOVEMENT, MEANS FOR MOVING SAID SHEET IN A PLANE ANGULAR WITH RESPECT TO THE HORIZONTAL AFTER SAID FIRST FOLD IS FORMED, MEANS FOR EFFECTING A SECOND TRANSVERSE FOLD IN SAID SHEET WHILE SAID SHEET IS MOVING IN SAID ANGULAR PLANE AND MEANS FOR THEREAFTER CHANGING THE DIRECTION OF MOVEMENT OF SAID TWICE FOLDED SHEET FROM SAID ANGULAR PLANE WHEREBY SAID SECOND FOLD IS POSITIONED IN ADVANCE OF SAID FIRST FOLD WITH RESPECT TO THE DIRECTION OF MOVEMENT, AND MEANS FOR DELIVERING IN A SECOND ANGULAR PLANE SAID TWICE FOLDED SHEET AS IT MOVES WITH SAID FIRST TRANSVERSE FOLD LYING REARWARDLY AND SAID SECOND TRANSVERSE FOLD LYING FORWARDLY WITH RESPECT TO THE DIRECTION OF SAID MOVEMENT AND SAID END EDGES LYING OVER SAID FIRST FOLD. 